Browsing by Author "Wicklund, Trude"

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    Descriptive sensory analysis, consumer liking and preference mapping for solar dried mango cv Dodo
    (IISTE, 2013) Mongi, Richard J.; Ndabikunze, Bernadette; Chove, Bernard; Wicklund, Trude
    Descriptive sensory characteristics, consumer liking and preference mapping of solar dried mango cv Dodo were investigated in this study. Three solar drying methods solar cabinet direct dryer (CDD), cabinet mixed-mode dryer (CMD) and Tunnel dryer (TD) were used to dry mango samples while fresh sample was used as control. Descriptive sensory analysis was performed by 15 trained panelists who used 6 descriptors to quantitatively describe the sensory characteristics of mango samples while 78 consumers were used to assess the degree of liking of products’ sensory attributes using nine-point hedonic scale. External preference mapping was performed by relating sensory data with hedonic responses. Randomized complete block research design with panelists and samples as main principal factors was used. The results showed significant differences (p<0.05) in mean intensity scores of whiteness, hardness and sweetness attributes with dried samples having higher values than their fresh counterparts. Fresh sample had significantly (p<0.05) higher colour intensity score than dried samples. The consumer study showed that, with exception of taste attribute, consumers showed significant (p<0.05) differences in colour, texture, mouth feel and overall acceptability with fresh samples having higher values than dried counterparts. Moreover, the preference mapping results showed colour and acidity (flavour) attributes to be the main driver for positive consumer preference for fresh samples. Among the drying methods, tunnel dryer showed a relatively close relationship with these attributes than cabinet dryers. In conclusion, solar drying has significant effect on sensory attributes of dried mango especially colour and flavour which is also dependent on the drying method employed. Therefore, selection of appropriate drying method which will retain these attributes is of greater importance for consumer acceptability and marketability.
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    Effect of solar drying methods on total phenolic contents and antioxidant activity of commonly consumed fruits and vegetable (mango, banana, pineapple and tomato) in Tanzania
    (Academic Journals, 2015) Mongi, Richard J.; Ndabikunze, Bernadette K.; Wicklund, Trude; Chove, Lucy M.; Chove, Bernard E.
    The effects of solar drying methods [Cabinet direct (CDD), cabinet mixed mode (CMD) and tunnel (TD) drying] on total phenolic content (TPC) and antioxidant capacities of commonly consumed fruits and vegetable in Tanzania were investigated. The TPC and FRAP in mangoes (Mangifera indica cv. Dodo, Viringe and Kent), bananas (Musa acuminata, cv. Kisukari, Kimalindi and Mtwike), pineapples (Ananas comosuss cv Smooth cayenne) and tomatoes (Lycopersicum esculentum cv. Tanya, Cal J and Onyx) were evaluated using Folin-Ciocalteu reagent and ferric reducing antioxidant power (FRAP) methods, respectively. There were significant (p<0.05) variations in TPC (mg GAE/100 g DM) and FRAP (μmol/100 g DM) among the fresh fruit and vegetable samples. The highest TPC was in tomato (476.6±8.6 - 538.9± 1.4) and lowest in banana (139.3±2.3 - 189.2±2.7). Drying methods had significant (p<0.05) effect on TPC and antioxidant values of the samples. All fresh samples had higher TPC levels but declined significantly in dried samples with the exception of tunnel dried tomatoes. Among the dried samples, the tunnel dried samples had less TPC loss (6-16%) than the cabinet dried samples (17-42%). The cabinet direct and mixed mode samples were not statistically different (p>0.05) from each other. However, tunnel dried samples had less FRAP loss (6-13%) which were statistically different (p<0.05) from the cabinet dried samples (14-56%). Percentage TPC and FRAP recoveries (%) differed significantly (P<0.05) between the varieties within the fruits/vegetable for both drying methods. A strong correlations between TPC and FRAP in both fresh (R2= 0.970) and dried samples (R2=0.8636) suggests that solar drying methods have significant effects on total phenolic contents and antioxidant activities of fruits and vegetables with tunnel drying method giving significantly less effects.